Autostereoscopic display devices are well known. A most common example comprises a two dimensional emissive liquid crystal display panel having a row and column array of display pixels acting as an image forming means to produce a display. An array of elongate lenticular lenses extending parallel to one another overlies the display pixel array and acts as a view forming means. Outputs from the display pixels are projected through these lenticular lenses, which function to modify the directions of the outputs.
The lenticular lenses are provided as a sheet of elements, each of which comprises an elongate semi-cylindrical lens element. The lenticular lenses extend in the column direction of the display panel, with each lenticular lens overlying a respective group of two or more adjacent columns of display pixels.
If lenticular lens is associated with two columns of display pixels, the display pixels in each column provide a vertical slice of a respective two dimensional sub-image. The lenticular sheet projects these two slices, and corresponding slices from the display pixel columns associated with the other lenticular lenses, to the left and right eyes of a user positioned in front of the sheet, so that the user observes a single stereoscopic image.
In other arrangements, each lenticular lens is associated with a group of three or more adjacent display pixels in the row direction. Corresponding columns of display pixels in each group are arranged appropriately to provide a vertical slice from a respective two dimensional sub-image. As a user's head is moved from left to right a series of successive, different, stereoscopic views are observed creating, for example, a look-around impression.
Another example of an imaging arrangement for use in this type of display is a barrier, for example with slits that are sized and positioned in relation to the underlying pixels of the display. In a two-view design, the viewer is able to perceive a 3D image if his/her head is at a fixed position. The barrier is positioned in front of the display panel and is designed so that light from the odd and even pixel columns is directed towards the left and right eye of the viewer, respectively.
According to a newly released “Transparent Display Technology and Market Forecast” report by Displaybank, transparent displays would debut the market for the first time in 2012 and sharply grow to create a $87.2 billion market by the year 2025, taking some market share from traditional flat panel displays, but also increasing the overall size of the market.
A transparent display is a type of display that has the characteristic of showing the background behind the display because the display itself has a certain level of transmittance. Transparent displays have many possible applications such as windows for buildings or automobiles and the display window in shopping malls.
There is not yet any technology for providing the proposed transparent displays with 3D viewing capability, and in particular not using the glasses-free lenticular lens or parallax barrier 3D approaches outlined above. A problem arises when attempting to combine a lenticular lens or a parallax barrier on top of a conventional transparent display. Not only the light generated by the display, but also the light transmitted through the display is affected by the lenticular lens or the parallax barrier preventing an undistorted view of the image behind the display.